Understanding the Indigo Dyeing Process

The king of blues and until the early 20 century the only blue, but still the only natural blue that will withstand any considerable amount of time. This dye has been being used dating as far back as 2000 BC, found in mummies tombs in Egypt it was highly prized and used regularly as is today yet many people would not realize there wardrobe contains at least a couple of garments and the process has remained the same since these ancient times.

Step 1:

MEASURE ALL INGREDIENTS IN INDIVIDUAL PLASTIC JUGS TO SPECIFIED WEIGHTS

Step 2:

FILL 10L BUCKET WITH WARM WATER 3 /4 FULL AND 2L JUG WITH COLD WATER

Step 3:

GET EVERYTHING IN ORDER IN PREPERATION FOR MIXING

Step 4:

DILUTE SALT IN HOT WATER AND ADD TO 10L BUCKET OF WARM WATER

DO THE SAME PROCESS WITH THE SODA ASH AND ADD TO 10L

Step 5:

PLACE MASK OVER NOSE AND MOUTH AND POUR THE HYDROXIDE INTO 2L JUG OF COLD WATER WHILST STIRRING WELL WITH WHISK UNTIL ALL IS MIXED

Step 6:

SCATTER AS IF MIXING FLOUR INTO CAKE, THE INDIGO VAT GRAINS INTO THE 2L JUG OF WATER/HYDROXIDE

Step 7:

THE LIQUID SHOULD TURN THE COLOUR OF PEA GREEN SOUP UNDERNEATH THE BLOOM OF INDIGO FROTH.

Step 8:

ADD THIS TO YOUR 10L BUCKET OF PREMIX, STIRRING UNTIL FULLY MIXED

LEAVE TO SETTLE FOR 20 - 30 MINUTES

Step 9: NEXT STAGE

SOAK YOUR DESIRED GARMENT/CLOTH IN BUCKET OF WATER TO ALLOW FABRIC TO BE FULLY POUROUS

Step 10:

READY TO PROCEED WITH DYEING, CLOTH ENTERS VAT AND IS GENTLY MOVED IN THE VAT FOR 2 MINS

Step 11:

REMOVE AND HANG ON LINE AND WATCH THIS MAGICAL OXIDATION MIRACLE OF NATURE TURN GREEN TO BLUE BEFORE YOUR EYES, THIS WILL TAKE ABOUT 10 - 20 MINS TO FULLY FIX THE INDIGO DYE. REPEATED DIPS WILL DEEPEN THE COLOUR AND THIS IS AN ESSENTIAL PROCESS TO MAKE THE DYE FAST AND LONG LASTING. WE RECOMMEND A MINIMUN OF 5 DIPS,

Step 12:

It is important to understand that this process relies on a vat which has been de-oxygenated and made alkaline by the ingredients. the vat is a delicate thing where the indigo cell requires a peaceful ride, any excess activity, eg splashing removing or thrusting cloth and creating bubbles will bring air into the vat and neutralise the indigo, therefore it is very important not to hurry and to be and to be gentle when moving cloth in the vat, taking particular care when lifting out so as not to disturb its particular balance, if treated carefully and covered at the end of each session the vat will be useful for many days. the process of fixing the dye substance happens entirely through its exposure in oxygen and rotating and moving pegs or opening folds will ensure an even dye coverage, because of this unique process blocks and folds can be placed onto the cloth to create patterning in resist as anything that doesn’t see sunlight or air stays its original colour the possibilities are infinite, see our next tutorial on shibori, the discipline of folding and clamping.

n.b this mix will give a mid to dark (see pic) indigo blue if you want a stronger shade you need to up the quantity of indigo grains keeping the other ingredients the same quantity. Likewise if you like a duck egg blue the amount of indigo vat grains you would need would be less, approx 5gm. experimentation will guide you. it is important to stress that despite quantity of indigo in vat you must always dip at least 5 times to get a lasting colour, the Japanese start at 25 dips!!

Very nice tut. The only big problem with indigo dyeing is that, the excess of tint remain over the fibers and came out for many many time during the use and the washes, i know that because i have an hakama and a kendogi made with japanese traditional indigo dyeing, in my searches on the net to find a way to fix the color i discovered that traditional metods like vinegar or chemical fixatives won't work.The traditional japanese old way is to use animal urine, cause the bacteria inside litteraly eat the excess colour. Some japanese people smell the dyed fabric for be sure that are made on the very old way.

I've used this recipe a couple of times now and it's worked really well. Lumo the Maker, I just have one question. This recipe doesn't require thiourea dioxide or sodium hydrosulfite as reducing agents, but seems to reduce the indigo anyway. Is caustic soda the reducing agent? And is this method still gentle enough for wool and silk?

this article helped me a lot for my project... a very nice way to make people understand about you own experiment. it helped me a lot. i was searching the information about the topic you have written and i have come across plenty of websites and blogs but i dint get the perfect thing which i wanted,and then i got your blog which completed my entire project of blue rebellion. i was asked to write even the steps how to do the indigo dyeing process. thanks a lot! and keep doing these kind of work so that if i need any kind of help from your blog i'll get it... :-)

this article helped me a lot for my project... a very nice way to make people understand about you own experiment. it helped me a lot. i was searching the information about the topic you have written and i have come across plenty of websites and blogs but i dint get the perfect thing which i wanted,and then i got your blog which completed my entire project of blue rebellion. i was asked to write even the steps how to do the indigo dyeing process. thanks a lot! and keep doing these kind of work so that if i need any kind of help from your blog i'll get it... :-)

Plant extraction of indigo requires several steps because the dye itself does not actually exist in nature. The chemical found in plant leaves is really indican, a precursor to indigo. The ancient process to extract indican from plant leaves and convert it to indigo has remained unchanged for thousands of years. In this process, a series of tanks are arranged in a step wise fashion. The upper-most tank is a fermentation vessel into which the freshly cut plants are placed. An enzyme known as indimulsin is added to hydrolyze, or break down, the indican into indoxyl and glucose. During this process carbon dioxide is given off and the broth in the tank turns a murky yellow. After about 14 hours, the resulting liquid is drained into a second tank. Here, the indoxyl-rich mixture is stirred with paddles to mix it with air. This allows the air to oxidize the indoxyl to indigotin, which settles to the bottom of the tank. The upper layer of liquid is siphoned away and the settled pigment is transferred to a third tank where it is heated to stop the fermentation process. The resultant mixture is filtered to remove impurities and dried to form a thick paste.

Historically, the Japanese have used another method which involves extracting indigo from the polygonum plant. In this process the plant is mixed with wheat husk powder, limestone powder, lye ash, and sake. The mixture is allowed to ferment for about one week to form the dye pigment which is called sukumo.

We are in the UK and the only person we know sells a minimum of kilogram amounts, although due to popularity of this instructable we were going to sell some smaller amounts of 100 grams. We can ship over if you so wish. Email me if your interested. lumolights@gmail.com

Nice article, but Woad is a traditional blue dye used in Asia and Europe until the indigo trade put it out of business, as indigo is a much stronger source of dye. I believe the color is identical to Indigo, but not as intense. Indigo definitely is not the only natural blue!

Yes woad is a natural blue, sorry bit misleading of me. I think what i meant to say is a natural blue that will last. Woad can be known to fade in a couple of years, where as indigo can last thousands.